Timing is not the best, they're super busy. I intend to follow up over winter and see if I can coax them into adding 6th to a Rocket.
Would be me buying a complete 2nd hand trans off ebay and shipping it off to get worked over and swap them out/in over a weekend.
So he'd need to make a gear/dog combo unit, another gear, cut two more slots in the input shaft for Snap Rings, as well as weld up the stock shift drum and remachine the grooves in it. All in, quite an expensive proposition, but, one that would truly set anyone's Rocket who did apart from the rest.